The prior art is already well developed with regard to the employment of bulldozer blades movably mounted on tractors. That type of prior art machine is widely used in bulldozing earth and other materials during construction, maintenance, and like work. U.S. Pat. No. 3,645,340 shows one example of the mounting of a bulldozer blade on a tractor.
In present day designing and building of tractors with bulldozer blades, one of the problems is providing a connector which suitably attaches the blade to the tractor such that the blade will have an articulate connection relative to the tractor, and this connection is the one which is located immediately behind the blade itself. That is, industry is concerned with mounting a bulldozer blade so that the blade can be movable relative to the support arm or like members extending from the tractor, and thus the blade can be tilted and pitched so that it is properly oriented relative to the ground or the material that it is working upon. Again, U.S. Pat. No. 3,645,340 shows an articulate type of connection for the blade, and such showing is particularly found in FIGS. 4, 5 and 6 of said patent. In that patent, the articulate mounting for the blade includes a swivel type of ball and socket assembly, and that assembly is shown to be secured in position by means of a snap ring which has one portion engaging the assembly and which has another portion disposed in a snap ring groove, all so that the assembly is held in a position at least as far as the arrangement in U.S. Pat. No. 3,645,340 is concerned. However, it has been found that the snap ring and groove type of restraining member for the swivel assembly mentioned is inadequate for the purpose desired. That is, in the prior art, the pivot ball bushing is retained in the support member or housing with a shoulder on the housing at one end of the bushing and with a snap ring at the other end of the bushing, as shown in said patent, and the requirements for the assembly are such that the snap ring does not always stay in its position in the groove, and thus the assembly is not secure. Further, the prior art retainer ring assembly commonly has the retainer ring move out of the groove and damage either the groove or the ring, in the process, and then reassembling the two never results in the desired tight assembly.
Accordingly, it is a general object of this invention to provide a pivot ball assembly for use in swivelly attaching a bulldozer blade to a support arm in a secure manner, and in a manner wherein the parts can be readily and easily manufactured, replaced as necessary, and reassembled, all for effecting a tight and snug assembly.
Another object of this invention is to provide a pivot ball assembly for use in swivelly attaching a bulldozer blade, whereby the assembly can be readily and easily manufactured and can be readily and easily disassembled and again assembled, all without damaging the parts and without resulting in any loose or weak assembly. Further, the present invention accomplishes the aforementioned objectives and it does so without requiring a complete structural change from the basic prior art assemblies wherein a support arm or member extends from the tractor and supports the assembly which in turn is connected with the back of the bulldozer blade. That is, only the pivot ball assembly itself is modified for achieving the present invention, and the attending members or adjacent elements of the overall assembly need not be altered in order to accommodate the improved pivot ball assembly of this invention.
Still further, where the prior art utilized a retainer ring in a groove, there was inherent end play in the arrangement, and thus the assembly could not be fully secure, and this condition was further exaggerated when the ring was dislodged or intentionally removed from the groove and then reassembled, and such looseness was inherent in the manufacturing practices and the required manufacturing tolerances between the parts. However, the present invention provides a pivot ball assembly wherein the parts can be fully secured in snug contact with each other, and further the parts can be readily disassembled and even replaced, and the subsequent assembly will result in a tight fit of all the parts. Still further, with the present invention as described herein, the pivot ball assembly provides for a greatly simplified machining and assembly process, and the close tolerances heretofore required and the difficult assembly process heretofore required are no longer required with the present invention.
Other objects and advantages will become apparent upon reading the following description in light of the accompanying drawings.